Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: AndersH on 24 July 2007, 10:47:08

Title: Gear change thump
Post by: AndersH on 24 July 2007, 10:47:08
Recently when changing up gear - I think probably 2nd to 3rd and especially in sport mode, and when the engine's cold the change will sometimes be accompanied by a thump which doesn't sound too good.  :'(
Hopefully something cheap and easy?  :-/
Title: Re: Gear change thump
Post by: Jimbob on 24 July 2007, 10:58:19
I sometimes get a bit of a clunk going from R to D

Have you done an gearbox oil and filter change? - Something I've been meaning to get done

Have you had it updated to the latest software? - Makes all changes a lot smoother.

Title: Re: Gear change thump
Post by: megaomega123 on 24 July 2007, 11:09:23
I am manual and I get a dull thump from reverse to 1st and when sat still at lights, when I put it in 1st. Always had it and doesnt sound horrible, just a thump.  :-?
Title: Re: Gear change thump
Post by: Entwood on 24 July 2007, 11:14:59
Quote

Have you had it updated to the latest software? - Makes all changes a lot smoother.


As a complete thicko and newbie ... how to I find out my software version and upgrade if needed ?? 99 V reg mini-facelift (I think)  Elite Auto. (window switches by gear lever, but HID and steering wheel audio controls ... so going by this ...  http://www.omegaowners.com/forum/YaBB.pl?num=1152617112  )

(bets the answer has something to do with an expensive visit to a Tech2)   :)

Regards

Entwood
Title: Re: Gear change thump
Post by: AndersH on 24 July 2007, 11:16:19
I had the firmware updated a few months ago, this has only really just started happening. The actual sound isn't that horrible, it's the sound of my wallet straining when I think it's an expensive problem that I don't like  ;D
I haven't changed the oil and filter, looked at the how to but looks a bit much for me, especially without pictures...
Title: Re: Gear change thump
Post by: Jimbob on 24 July 2007, 11:57:35
Quote
Quote

Have you had it updated to the latest software? - Makes all changes a lot smoother.


As a complete thicko and newbie ... how to I find out my software version and upgrade if needed ?? 99 V reg mini-facelift (I think)  Elite Auto. (window switches by gear lever, but HID and steering wheel audio controls ... so going by this ...  http://www.omegaowners.com/forum/YaBB.pl?num=1152617112  )

(bets the answer has something to do with an expensive visit to a Tech2)   :)

Regards

Entwood

Right 1st time
You cant really check yourself, and certainly cant update without tech2, find a 'cheap' dealer, or the recommended approach of see the boy!

for the gearbox, 1st port of call is ALWAYS an oil and filter change
Title: Re: Gear change thump
Post by: TheBoy on 24 July 2007, 18:48:12
Quote
Recently when changing up gear - I think probably 2nd to 3rd and especially in sport mode, and when the engine's cold the change will sometimes be accompanied by a thump which doesn't sound too good.  :'(
Hopefully something cheap and easy?  :-/
Consider changing atf asap...
Title: Re: Gear change thump
Post by: TheBoy on 24 July 2007, 18:49:42
Quote
Quote

Have you had it updated to the latest software? - Makes all changes a lot smoother.


As a complete thicko and newbie ... how to I find out my software version and upgrade if needed ?? 99 V reg mini-facelift (I think)  Elite Auto. (window switches by gear lever, but HID and steering wheel audio controls ... so going by this ...  http://www.omegaowners.com/forum/YaBB.pl?num=1152617112  )

(bets the answer has something to do with an expensive visit to a Tech2)   :)

Regards

Entwood
I'm gonna guess that on a 99, you will likely have version 05 software on your box.  Good news is, you'll have a GS820 ECU, which is flashable.  Bad news is it needs a Tech2.
Title: Re: Gear change thump
Post by: Entwood on 24 July 2007, 22:48:57
@TheBoy

Thanks for that info ... methinks that as I've had it 6 years and it seems to be working OK .. I'll opt for the "if it ain't broke don't fix it" approach, unless there is some over-riding reason for the upgrade ?? like 60+ mpg  :)

yeah .. I live in a dream world sometimes !!!  ;D ;D
Title: Re: Gear change thump
Post by: RonaldMcBurger on 24 July 2007, 22:54:30
I did get 140mpg out of one Omega, but it was on the back of an RAC truck! >:(

Gearbox thump. Mmmmmmm. First thought is change that fluid PRONTO. brand spanking new dexron III will make it all lubbly jubbly again. Take both sumps off, clean THOROUGHLY and reassemble. Fill with ATF then run and top up until flowing out the filler again.

Drive and marvel at the difference.
Title: Re: Gear change thump
Post by: Taxi_Driver on 25 July 2007, 00:11:58
Quote
@TheBoy

Thanks for that info ... methinks that as I've had it 6 years and it seems to be working OK .. I'll opt for the "if it ain't broke don't fix it" approach, unless there is some over-riding reason for the upgrade ?? like 60+ mpg  :)

yeah .. I live in a dream world sometimes !!!  ;D ;D

Gearbox upgrade apparently makes gearbox changing smoother.....mines pretty smooth most of the time...occansionaly it thumps....but is on nearly 100k now and never had it oil changed.....if i were you a visit to TB....dunno where in wilts you are but can be only a hour or two drive.....would be worth a trip for a few cases of stella  :y
Title: Re: Gear change thump
Post by: AndersH on 25 July 2007, 09:39:38
Thanks for everyone's input, seems I need to change the fluid then! Can someboday tell me where these sumps are, (a photo would be amazing!) where I stick me dexron III and if an idiot like me can manage this?
Title: Re: Gear change thump
Post by: Entwood on 25 July 2007, 09:49:30
Don't know id I'm breaking any rules ... written or unwritten.... if so I apologise.....   :-?

But my research has found this which may help Mambafia ...

http://www.vauxhallownersnetwork.co.uk/showthread.php?t=62232


My question is .... how much "ground clearance" does this need to drop the sumps ? I'll be doing the job purely on axle stands if I DIY...

Regards

Entwood
Title: Re: Gear change thump
Post by: Jimbob on 25 July 2007, 09:58:26
That doesn't sound as hard as I expected!
Once I buy some stands, I may have a go at that myself rather than pay.
Trouble is my drive is too slopey, so would have to do it on the road :(
Title: Re: Gear change thump
Post by: Jimbob on 25 July 2007, 10:00:46
Anyone got a price for all the parts?

Then just hope you dont find pieces of broken thrust washer  :o
Title: Re: Gear change thump
Post by: TheBoy on 25 July 2007, 10:41:40
OK, easy enough job, basically, remove filler plug, both sumps, then filter. Reverse method to refit, ensuring mating surfaces are clean.

Refill (Mark_DTM has a method in Maint Guides), and enjoy
Title: Re: Gear change thump
Post by: TheBoy on 25 July 2007, 10:42:20
£38 for filter and the 2 gaskets from JPAT

£20 for 5l of Dexron III from Halfords, need about 7l
Title: Re: Gear change thump
Post by: Dave-C on 25 July 2007, 19:10:28
Quote
£38 for filter and the 2 gaskets from JPAT

£20 for 5l of Dexron III from Halfords, need about 7l


Mark DTM suggested to me, to remove and clean the filter out...  White Spirit was suggested, the crap did just come out..  A noticable change on completion, I think I paid £18 for the gaskets from VX  via TC...  Mark suggests using a sealant instead of gaskets...  What I'm getting to, is that it can be done much cheaper if budget is an issue...  As TB says DEXIII (THREE) £20

Go on, go for it and good luck..

DC
Title: Re: Gear change thump
Post by: TheBoy on 25 July 2007, 19:14:37
Quote
Quote
£38 for filter and the 2 gaskets from JPAT

£20 for 5l of Dexron III from Halfords, need about 7l


Mark DTM suggested to me, to remove and clean the filter out...  White Spirit was suggested, the crap did just come out..  A noticable change on completion, I think I paid £18 for the gaskets from VX  via TC...  Mark suggests using a sealant instead of gaskets...  What I'm getting to, is that it can be done much cheaper if budget is an issue...  As TB says DEXIII (THREE) £20

Go on, go for it and good luck..

DC
Yes, MDTM cleaned the filter on the TD, and used sealant instead of gaskets. Gearbox let go about 2 weeks later (obviously completely unrelated, the reason I changed fluid was due to bad changes), but no leaks etc up until that point...

Ensure the cork gasket bit near filter doesn't come adrift...
Title: Re: Gear change thump
Post by: Dave-C on 25 July 2007, 19:38:47
Quote
Quote
Quote
£38 for filter and the 2 gaskets from JPAT

£20 for 5l of Dexron III from Halfords, need about 7l


Mark DTM suggested to me, to remove and clean the filter out...  White Spirit was suggested, the crap did just come out..  A noticable change on completion, I think I paid £18 for the gaskets from VX  via TC...  Mark suggests using a sealant instead of gaskets...  What I'm getting to, is that it can be done much cheaper if budget is an issue...  As TB says DEXIII (THREE) £20

Go on, go for it and good luck..

DC
Yes, MDTM cleaned the filter on the TD, and used sealant instead of gaskets. Gearbox let go about 2 weeks later (obviously completely unrelated, the reason I changed fluid was due to bad changes), but no leaks etc up until that point...

Ensure the cork gasket bit near filter doesn't come adrift...

Good point, kept a close eye on mine whilst W.I.P..

DC
Title: Re: Gear change thump
Post by: AndersH on 26 July 2007, 07:51:41
Just been to an autobox specialist and they quoted £88 to get the fluid and filter changed and the codes read so am thinking of attempting this myself. I don't get any codes with the paperclip test, are there different codes for the gearbox that only Tech II can read?
Also does anyone have any part numbers for the gaskets?

Thanks!
Title: Re: Gear change thump
Post by: Dave-C on 26 July 2007, 18:24:05
Quote
Just been to an autobox specialist and they quoted £88 to get the fluid and filter changed and the codes read so am thinking of attempting this myself. I don't get any codes with the paperclip test, are there different codes for the gearbox that only Tech II can read?
Also does anyone have any part numbers for the gaskets?

Thanks!


To my knowledge, AR25 & AR35 have the same gaskets, they have a fore and an aft gasket,  your dealer will find them easy on the EPC...  others may know different...  DC
Title: Re: Gear change thump
Post by: TheBoy on 26 July 2007, 19:12:12
Quote
Just been to an autobox specialist and they quoted £88 to get the fluid and filter changed and the codes read so am thinking of attempting this myself. I don't get any codes with the paperclip test, are there different codes for the gearbox that only Tech II can read?
Also does anyone have any part numbers for the gaskets?

Thanks!
Not a bad price tbh...

Gaskets and filter, £38 from JPAT (much cheaper than dealer), Dexron III £20 from Halford s for 5l, you need about 7l

Need Tech2 to read codes...